Door locking mechanism



Aug. 30, 1966 R. J. LYNN ETAL DOOR LOCKING MECHANISM 2 Sheets-Sheet 1 Filed July 29, 1964 DOOR OPERATOR INVENTORS ROBERT J LYNN KRISTUPAS DAUGIRDAS CLARENCE L, WANLUND AT TO RNEY Aug. 30, 1966 R. J. LYNN ETAL DOOR LOCKING MECHANISM 2 Sheets-Sheet 2 Filed July 29, 1964 FIGA INVENTO RS ROBERT J. LYNN KRISTUFAS DAUGIRDAS CLARENCE L. WANLUND WlLLlA W- PA KS imww= ATTORNEY United States Patent 3,269,058 DOOR LOCKING MECHANISM Robert J. Lynn, Morton Grove, Kristupas Daugirdas, Wilmette, Clarence L. Wanlund, Evanston, and William W.

Parks, Glenview, 11]., assignors to Vapor Corporation,

Chicago, 111., a corporation of Delaware Filed July 29, 1964, Ser. No. 385,946 11 filaims. (Cl. 49-414) This invention relates in general to a door operator for a public conveyance, such as subways, streetcars, and the like, and more particularly to a door locking mech anism for locking the door in closed position and actuatable during the normal operation of the door operator.

The locking mechanism of the present invention avoids the complexity and added structure heretofore employed in such locking mechanisms thereby reducing maintenance requirements and initial cost, while yet ultimately providing a more reliable locking mechanism.

The presently employed locking mechanisms are generally of the solenoid-actuated type, and are mounted directly on the door operator such as is shown in the Daugirdas Patent 3,104,098, issued September 17, 1963. Quite obviously, a solenoid controlled lock requires complicated circuitry including relays, switches and contacts, that multiplies the complexity to the structure of the operator and associated controls. Additionally, long rods are employed to connect linkages of the solenoid operated lock to the doors.

The mechanical lock of the present invention is incorporated into the door operator system of public conveyances to provide a secondary door lock for safety purposes. For example, should the linkages of the rods driving the doors and holding the doors closed break while the conveyance is in transit, the secondary mechanical lock will prevent the doors from opening should a person lean against the door. Further, the mechanical lock of the present invention is provided with a simple switch that indicates to the operator when the door lock is not in locked position if the conveyance is stopped at a station and warns the operator against starting. Or the safety switch on the locking mechanism may be directly tied into the electrical system of the conveyance to prevent start up if the lock is in unlocked position. Thus, the door locking mechanism would indicate to the motorman or operator whether something is caught in the door and is preventing it from being closed if the door locking mechanism has not moved to locking position.

Accordingly, it is an object of the present invention to provide a new and improved door locking mechanism for public conveyances which is ruggedly and simply constructed, compact in size, economical to manufacture, and substantially maintenance free.

Another object of the present invention is to provide a door locking mechanism for doors in public conveyances that is capable of securely locking the door when the door is closed under normal conditions.

A further object of this invention resides in the provision of a door locking mechanism for use with a door operator in a public conveyance that is capable of keeping' the door safely locked in the event that the control linkage from the door operator becomes disabled.

A still further object of this invention is in the provision of a door locking mechanism for public conveyances to be employed with a door operator that is capable of opening and closing the door, wherein the locking mechanism can only unlock when the door is opened under the power of the door operator.

Another object of this invention is to provide a door locking mechanism for doors on public conveyances capable of permitting the door to open a predetermined distance by applying a force of given magnitude to the door when the door is in unlocked position.

Still another object of this invention is in the provision of a locking mechanism for doors on public conveyances that is capable of providing indication to the motorman or operator of the conveyance that the door is safely locked, and conversely to indicate when the door is in unlocked or opened position.

A further object of this invention is to provide an improved door locking mechanism for use in opening and closing sliding doors of passenger carrying vehicles, such as streetcars, subways and other trains, buses, and the like.

Other objects, features and advantages of the invention will be apparent from the following detailed disclosure, taken in conjunction with the accompanying sheets of drawings, wherein like reference numerals refer to like parts, in which:

FIG. 1 is a side elevational view of the door locking mechanism of the present invention, partly diagrammatic and fragmentary, and showing the door in fully closed and locked position;

FIG. 2 is a top plan view of FIG. 1;

FIG. 3 is a side elevational view of the locking mechanism shown in FIG. 1 with the door and locking mechanism parts positioned at the moment of unlocking, and with some parts omitted for purposes of clarity and some parts shown in phantom; and

FIG. 4 is a view similar to FIG. 3 showing the mechanical lock in unlocked and toggled out positions.

Referring now to the drawings and particularly to FIGS. 1 and 2, the door locking mechanism of the present invention is shown in locked position with the door in closed position, wherein the door is generally designated by the numeral 10 and the locking mechanism is generally designated by the numeral 11. While the door 10 is shown as being arranged between an interior door post 12 and an outer door post 13, it can be appreciated that it is not necessary to show any additional structure of the public conveyance having the door 10 mounted for opening and closing a door opening in the conveyance. Further, the door 10 may only operate to close half of the door opening while a similar door oppositely disposed would close the other half of the door opening. It should be further appreciated that the door 10 slides between open and closed positions and between the inner and outer walls of the public conveyance.

A somewhat U-shaped bracket 14 is suitably secured to the edge of the door 10 and provided with an opening 15 freely receiving therein a door control rod 16 of the door operator 17. While no details are shown of the door operator 17, it may be of any suitable type such as the one shown in the aforesaid patent and which is capable of transmitting reciprocal movement of the door control rod 16 for driving the door 10 between open and closed positions. A collar 18 is secured to the end of the door control rod 16 at the inside of the bracket 14 to prevent the door control rod from moving out of the bracket 14. A leaf spring 19 secured to the door 1% applies a force to the end of the door control rod 16 so that it normally takes the position relative to the bracket 14 as shown in FIG. 1. However, the spring 19 permits movement of the door 10 in the direction toward the door operator a distance equal to the distance between the end of the door control rod and the door taking into consideration the spring 19 so that if the person were to catch a part of his body or clothing between the door 11) and an opposing door or the door 10 and the edge of the door opening, it is possible to apply a force to the door 10 and move it a slight distance toward the door operator even after it has attained a locked position so that the part of the body of the person and/or his clothing can be removed. Thus, the door is normally driven between open and closed positions by the door control rod 16 of the door operator 17 and by the impositive coupling between the door control rod and the bracket 14.

The door locking mechanism 11 includes a locking pawl 20 pivotally carried on a stub shaft 21 that is fixed to a mounting plate 22. The mounting plate 22 is in turn secured to a plate 23 that is fixed to the inner door post 12. A lock pin 24 having a portion 25 extending perpendicular to the path of door movement coacts with the locking pawl 20 for locking the door in closed position.

The locking pawl includes longitudinally spaced lugs 26 and 27 that coact with the lock pin 24 and permit limited movement of the door 10 toward open position against the biasing of the spring 19, but prevent opening of the door beyond that predetermined distance should the door control rod 16 be broken and eliminate the connection between the door 10 and the door operator 17. In the latter example, the door It) would be movable to a position where the portion of the lock pin 24 would engage the lug 27 of the locking pawl 20.

A lock pawl latch 28 limits the movement of the look ing pawl 20 when the locking mechanism 11 is in locked position to prevent movement of the locking pawl lug 27 I to a position that would permit the lock pin 24 to move beyond the locking mechanism 11. The lock pawl latch 28 is pivotally mounted on a stub shaft 29 carried on the mounting plate 22. A spring 30, connected at one end to a pin 31 fixed to the mounting plate 22 and at the other end to a pin 32 fixed to the upper end of the lock pawl latch 29, holds the lock pawl latch 28 in the position shown in FIG. 1 when the locking mechanism is in locked position. The upper end 33 of the lock pawl latch 28 is aligned with a portion 34 of the locking pawl 20 when the r locking mechanism is in locked position to prevent movement of the locking pawl 20 to a position that would permit free movement of the lock pin 24 beyond the locking mechanism. The lock pawl latch 28 is held by the spring against a stop pin 35.

An actuating cam 36 in the form of a collar is secured to the door control rod 16 for engagement with opening and closing cams 37 and 38 on the lock pawl latch 28. As the door operator is energized to open the door 10, it will cause movement of the door control rod 16 to the left as seen in FIG. 1 in a direction to pull the door 10 to an open position relative to the door opening of the public conveyance. During movement of the door control rod in this direction, the actuating cam 36 thereon engages the opening cam 37 on the lock pawl latch 28 and causes the lock pawl latch to pivot about the shaft 29 against the restraining action of the spring 30 in a counterclockwise direction as shown particularly by FIGS. 3 and 4. At the same time, the lock pin 24 is moving within the space between the lugs 26 and 27 and as the lock pin portion 25 moves away from the lug 26, it permits the locking pawl 20 to pivot by its own weight counterclockwise about the stub shaft 21. However, the locking pawl 20 is initially stopped from further movement by the lock pawl latch 28 when the portion 34 of the locking pawl 20 engages the upper end 33 of the lock pawl latch. When the lock pawl latch 28 reaches the quick release position as shown in FIG. 3, the locking pawl drops down against a pawl stop pin 39 by its own weight to remove the lug 27 from the path of the lock pin portion 25 and thereafter permit further opening of the door 10. As the door continues to open, the actuating cam 36 on the door control rod 16 continues to cause rotation of the lock pawl latch 28 until the spring 30 passes over the center of rotation of the lock pawl latch, and thereby causes the latch to snap against the latch stop pin 40 as shown in phantom in FIG. 4. The quick release position of the locking pawl 20 wherein it rests against the pawl stop 39 is shown in solid lines in FIG. 4. Following the movement of the lock pawl latch 28 to the position against the 4 latch stop 40, the actuating cam 36 is now clear of the opening cam 37 on the lock pawl latch 28 and the door is free to open under the power of the door operating device 17.

In moving the locking mechanism 11 to lock position, the door operator advances the door 10 toward the closed position and when the actuating cam 36 engages the closing cam 38 on the lock pawl latch 28, it causes rotation of the lock pawl latch 28 about its shaft 29 in a counterclockwise direction until the spring 30 passes over the center of rotation of the latch and causes the latch to snap into the position shown in solid lines in FIG. 4. The actuating cam 36 is now free to clear the opening cam 38 on the lock pawl latch. As the door continues to move to closed position under the power of the door operator 17, the portion 25 of the lock pin 24 comes into contact with the lug 26 on the locking pawl 20 and causes the locking pawl 20 to pivot clockwise about the shaft 21. When the locking pawl 20 has reached the position shown in solid lines in FIG. 3, the spring 30 then causes the lock pawl latch 28 to snap against the latch stop pin 35.

A shielded mercury switch 41 is mounted on the lock pawl latch 28 and operates to indicate to the motorman or conductor when the door 10 is safely locked in position, and conversely, when the door 10 is in unlocked position relative to the locking mechanism 11. This switch may be connected into the circuitry of the power for driving the conveyance so as to prevent movement of the conveyance until this switch is closed, or it may be merely connected to a pilot light 42 (FIG. 1) that is mounted on the motormans panel. Or the switch could be connected into the power of the vehicle and also operate the pilot light 42. In any event, it is intended that the switch 41 give some indication to the motonman as to whether the locking mechanism 11 has attained the locked position thereby making it safe to proceed. Preferably, the switch 41 breaks at a point slightly before the quick release position shown in phantom lines in FIG. 3, al though it could be adjusted to break at any desired time. Conversely, the switch would break, as it was being moved by the lock pawl latch 28, between the quick release position and the position against the stop pin 35. It should be appreciated that any other type of switch may be employed if so desired.

It will be understood that modifications and variations may be etfected without departing from the scope of the novel concepts of the present invention, but it understood that this application is to be limited only by the scope of the appended claims.

The invention is hereby claimed as follows:

1. In a vehicle having a door opening and a door selectively movable between open and closed positions relative to said door opening, a door operator having a control rod drivingly connected to said door, and a locking mechanism for locking the door in closed position, said locking mechanism comprising, a lock pin secured to said door, a locking pawl movable to block movement of said lock pin when the door is in substantially fully closed position to thereby lock the door against movement to open position, a lock pawl latch coacting with said locking pawl and movable to selectively prevent movement of said locking pawl when it is in position to block movement of said lock pin and permitting said locking pawl to move to a position to permit movement of said locking pawl and thereafter said lock pin, means for impositively holding said lock pawl latch in blocking and permitting positions, and means on said control rod coacting with said lock pawl latch and driving said lock pawl latch between blocking and permitting poistions during opening and closing of said door by said door operator.

2. In a vehicle having a door opening and a door selectively movable between open and closed poistions relative to said door opening, a door operator having a control rod drivingly connected to said door, and a lock ing mechanism for locking the door in closed position, said locking mechanism comprising, a lock pin secured to said door, a locking pawl movable to block movement of said lock pin when the door is in substantially fully closed position to thereby lock the door against movement to open position, a lock pawl latch coacting with said locking pawl and movable to selectively prevent movement of said locking pawl when it is in position to block movement of said lock pin and permitting said locking pawl to move to a position to permit movement of said locking pawl and thereafter said lock pin, means for impositively holding said lock paiwl latch in blocking and permitting positions, cam means on said lock pawl latch, and cam means on said control rod coacting with said cam means on said lock pawl latch for driving said lock pawl latch between blocking and permitting positions during opening and closing of said door by said door operator.

3. In a vehicle having a door opening and a door selectively movable between open and closed positions relative to said door opening, a door operator having a con- .trol rod drivingly connected to said door, and a locking mechanism lfOI locking the door in closed position, said locking mechanism comprising, a lock pin secured to said door, a locking pawl movable to block movement of said lock pin when the door is in substantially fully closed position to thereby lock the door against movement to open position, a lock pawl latch coacting with said locking pawl and movable to selectively prevent movement of said locking pawl when it is in position to block movement of said lock pin and permitting said locking pawl to move to a position to permit movement of said locking pawl and thereafter said lock pin, means for impositively holding said lock pawl latch in blocking and permitting positions, cam means on said lock pawl latch, cam means on said control rod coacting with said carn means on said lock pawl latch for driving said lock pawl latch between blocking and permitting positions during opening and closing of said door by said door operator, and signal means on said lock pawl latch operable upon movement of said latch to a position that will permit movement of said locking pawl to a position to permit the lock pin free movement so that the door may open.

4. In a vehicle having a door opening and a door selectively movable between open and closed positions relative to said door opening, a door operator having a control rod and capable of reciprocating same, said door having a bracket secured thereto with an opening to freely receive said control rod, stop means on said control rod to prevent withdrawal of said rod from said opening, a spring mounted on said door and acting against the end of the control rod to continually urge the stop means against said bracket, said locking mechanism comprising, a lock pin secured to said door, a locking pawl movable to block movement of said lock pin when the door is in substantially fully closed position to there- 'by lock the door against movement to open position, a lock pawl latch coacting with said locking pawl and movable to selectively prevent movement of said locking pawl when it is in position to block movement of said lock pin and permitting said locking pawl to move to a position to permit movement of said locking pawl and thereafter said lock pin, means for impositively holding said lock pawl latch in blocking and permitting positions, and means on said control rod coacting with said pawl latch and driving said lock pawl latch between blocking and permitting positions during opening and closing of said door by said door operator.

5. In a vehicle having a door opening and a door selectively movable between open and closed positions relative to said door opening, a door operator having a control rod drivingly connected to said door, and a locking mechanism for locking the door in closed position, said locking mechanism comprising, a lock pin secured to said door, a locking pawl movable to block movement of said lock pin when the door is in substantially fully closed position to thereby lock the door against movement to open position, a lock pawl latch coacting with said locking pawl and movable to selectively prevent movement of said locking pawl when it is in position to block movement of said lock pin and permitting said locking pawl to move to a position to permit movement of said locking pawl and thereafter said lock pin, means for impositively holding said lock pawl latch in blocking and permitting positions, means on said control rod coacting with said lock pawl latch and driving said lock pawl latch between blocking and permitting positions during opening and closing of said door by said door operator, and switch means operable by said locking mechanism to indicate to the operator of the vehicle when the door is in open and unlocked or closed and locked position.

6. In a vehicle having a door opening and a door selectively movable between open and closed positions relative to said door opening, a door operator having a control rod drivingly connected to said door, and a locking mechanism for locking the door in closed position, said locking mechanism comprising, a lock pin secured to said door and having a portion extending perpendicular to the path of movement of said door, a locking pawl pivotally movable between lock position to block substantial movement of said lock pin portion when the door is in substantially fully closed position to thereby lock the door against movement to open position and unlock position to permit movement of said lock pin portion and the opening of said door, a lock pawl latch coacting with said locking pawl and movable to block said locking pawl in lock position and to permit said locking pawl to move to unlock position, means for impositively holding said lock pawl latch in blocking and permitting positions, and means on said control rod coacting with said lock pawl latch and driving said lock pawl latch between blocking and permitting positions during opening and closing of said door by said door operator.

7. In a vehicle having a door opening and a door selectively movable between open and closed positions relative to said door opening, a door operator having a control rod drivingly connected to said door, and a locking mechanism for locking the door in closed position, said locking mechanism comprising, a lock pin secured to said door and having a portion extending perpendicular to the path of movement of said door, a locking pawl pivotally movable between lock position to block substantial movement of said lock pin portion when the door is in substantially fully closed position to thereby lock the door against movement to open position and unlock position to permit movement of said lock pin portion and the opening of said door, said locking pawl having spaced closing and blocking lugs whereby said lock pin portion engages said closing lug upon movement of said door into closed position to pivot said locking pawl to a position to bring the blocking lug into the path of said lock pin portion, a lock pawl latch coacting with said locking pawl and movable to block said locking pawl in lock position and to permit said locking pawl to move to unlock position, means for impositively holding said lock pawl latch in blocking and permitting position, and means on said control rod coacting with said lock pawl latch and driving said iock pawl latch between blocking and permitting positions during opening and closing of said door by said door operator.

8. In a vehicle having a door opening and a door selectively movable between open and closed positions relative to said door opening, a door operator having a control rod drivingly connected to said door, and a locking mechanism for locking the door in closed position, said locking mechanism comprising, a lock pin secured to said door and having a portion extending perpendicular to the path of movement of said door, a locking pawl pivotally movable between lock position to block substantial movement of said lock pin portion when the door is in substantially fully closed position to thereby lock the door against movement to open position and unlock position to permit movement of said lock pin portion and the opening of said door, a lock pawl latch coacting with said locking pawl and pivotally movable to block said locking pawl in lock position and to permit said locking pawl to move to unlock position, an over center mounted spring holding said lock pawl latch in blocking and permitting positions, and means on said control rod coacting with said lock pawl latch and driving said lock pawl latch between blocking and permitting positions during opening and closing of said door by said door operator.

9. In a vehicle having a door opening and a door selectively movable between open and closed positions relative to said door opening, a door operator having a control rod drivingly connected to said door, and a locking mechanism for locking the door in closed position, said locking mechanism comprising, a lock pin secured to said door and having a portion extending perpendicular to the path of movement of said door, a locking pawl pivotally movable between lock position to block substantial movement of said lock pin portion when the door is in substantially fully closed position to thereby lock the door against movement to open position and unlock position to per mit movement of said lock pin portion and the opening of said door, a lock pawl latch coacting with said locking pawl and movable to block said locking pawl in lock position and to permit said locking pawl to move to unlock position, means for impositively holding said lock pawl latch in blocking and permitting positions, cam means on said lock pawl latch, and cam means on said control rod coacting with said cam means on said lock pawl latch for driving said lock pawl latch between blocking and permitting positions during opening and closing of said door by said door operator.

10. In a vehicle having a door opening and a door selectively movable between open and closed positions relative to said door opening, a door operator having a control rod drivingly connected to said door, and a locking mechanism for locking the door in closed position, said locking mechanism comprising, a lock pin secured to said door and having a portion extending perpendicular to the path of movement of said door, a locking pawl pivotally movable between lock position to block substantial movement of said lock pin portion when the door is in substantially fully closed position to thereby lock the door against movement to open position and unlock position to permit movement of said lock pin portion and the opening of said door, a lock pawl latch coacting with said locking pawl and pivotally movable to block said locking pawl in lock position and to permit said locking pawl to move to unlock position, an over center mounted spring holding said l-ock pawl latch in blocking and permitting positions, cam means on said lock pawl latch, and cam means on said control rod coacting with said cam means on said lock pawl latch for operating said lock pawl latch between blocking and permitting positions during opening and closing of said door by said door operator.

11. In a vehicle having a door opening and a door selectively movable bet-ween open and closed positions relative to said door opening, a door operator having a control rod drivingly connected to said door, and' a locking mechanism for locking the door in closed position, said locking mechanism comprising, a lock pin secured to said door and having a portion extending perpendicular to the path of movement of said door, a locking pawl pivotally movable between lock position to block substantial movement of said lock pin portion when the door is in substantially fully closed position to thereby lock the door against movement to open position and unlock position to permit movement of said lock pin portion and the opening of said door, a lock pawl latch coacting with said locking pawl and pivotally movable to block said locking pawl in lock position and to permit said locking pawl to move to unlock position, an over center mounted spring holding said lock pawl latch in blocking and permitting positions, cam means on said lock pawl latch, cam means on said control rod coacting with said cam means on said lock pawl latch for operating said lock pawl latch between blocking and permitting positions during opening and closing of said door by said door operator, and switching means on said lock pawl latch indicating to the operator of the vehicle when the door is in open and unlocked or closed and locked position.

References Cited by the Examiner UNITED STATES PATENTS 11/1938 Steele 268-3 X 9/1963 Daugirdas 26853 

1. IN A VEHICLE HAVING A DOOR OPENING AND A DOOR SELECTIVELY MOVABLE BETWEEN OPEN AND CLOSED POSITIONS RELATIVE TO SAID DOOR OPENING, A DOOR OPERATOR HAVING A CONTROL ROD DRIVINGLY CONNECTED TO SAID DOOR, AND A LOCKING MECHANISM FOR LOCKING THE DOOR IN CLOSED POSITION, SAID LOCKING MECHANISM COMPRISING, A LOCK PIN SECURED TO SAID DOOR, A LOCKING PAWL MOVABLE TO BLOCK MOVEMENT OF SAID LOCK PIN WHEN THE DOOR IS IN SUBSTANTIALLY FULLY CLOSED POSITION TO THEREBY LOCK THE DOOR AGAINST MOVEMENT TO OPEN POSITION, A LOCK PAWL LATCH COACTING WITH SAID LOCKING PAWL AND MOVABLE TO SELECTIVELY PREVENT MOVEMENT OF SAID LOCKING PAWL WHEN IT IS IN POSITION TO BLOCK MOVEMENT OF SAID LOCK PIN AND PERMITTING SAID LOCKING PAWL TO MOVE TO A POSITION TO PERMIT MOVEMENT OF SAID LOCKING PAWL AND THEREAFTER SAID LOCK PIN, MEANS FOR IMPOSITIVELY HOLDING SAID LOCK PAWL LATCH IN BLOCKING AND PERMITTING POSITIONS, AND MEANS ON SAID CONTROL ROD COACTING WITH SAID LOCK PAWL LATCH AND DRIVING SAID LOCK PAWL LATCH BETWEEN BLOCKING AND PERMITTING POSITIONS DURNG OPENING AND CLOSING OF SAID DOOR BY SAID DOOR OPERATOR. 